An apparatus for teaching defensive driving includes a hub unit removably attachable to an axle of a wheel of a vehicle, and a housing unit. The housing unit includes a swing arm member pivotally affixed therewithin, a wheel-height adjusting mechanism, and at least one wheel assembly swiveling along a vertical axis and affixed at a bottom end of the housing unit. The swing arm member includes a unit for fittingly engaging a portion of the hub unit and a height adjustable member. The height adjusting mechanism is operatingly coupled to the height adjustable member to adjust a height of the wheel relative to a surface of a road, thereby adjusting a friction level between the wheel and the road surface.